With the spread of various kinds of mobile devices such as a mobile phone, various services using mobile devices are available. One such service is a location information service providing a service relating to the current location of a locating target person who may be or may not be a user of this service. This location information service is for example a current location searching service of a PHS phone, a current location searching service of locating a locating target person such as a senior person or a child, and a service of delivering information relating to the current location.
To carry out this kind of location information service, it is necessary to locate the current location of the locating target person. This location is usually conducted by giving a locating target person a mobile device such as a mobile terminal, a Personal Handy-phone System (PHS) phone, or a Personal Digital Assistant (PDA) with GPS function and by exchanging signals for locating between a location device and the mobile device.
However, the locating methods differ depending on the mobile devices of locating target persons. Hence, location information service providers at present are able to provide a location information service to only locating target persons having a particular kind of mobile device. Therefore, to provide location information service to many locating target persons having various kinds of mobile device, a service provider has to prepare location means for various mobile devices; this increases costs for providing location information service. Also, there are cases where necessary representing format of location information is different depending on the content of the location information service. For example, location information expressed by latitude and longitude is preferable when providing one kind of service, and location information expressed by address (character string) is preferable when providing another kind of service. In this case, the service provider has to have means for generating location information with suitable representing format for each service.
As described above, provision of location information services places a great burden on service providers.
Although the contents of service provided by various service providers are different, there are only limited kinds of obtaining methods for location information necessary to service providers, and it is conceivable that there are many methods that can be shared by service providers. However, service providers install facilities for obtaining and managing location information of users, resulting in investing in the same facilities.